Josh Peck, left, Josh Hutcherson and Chris Hemsworth star in the reboot of the cult classic 'Red Dawn.' / Ron Phillips, Film District

by Claudia Puig, USA TODAY

by Claudia Puig, USA TODAY

Yet another unnecessary reboot hits theaters this week, with a few good action sequences, but marred by one-dimensional characters and excessively shaky camera work.

Early in Red Dawn (** out of four; rated PG-13; opening Wednesday nationwide) residents of Spokane, Wash., wake up to paratroopers floating in, as if suspended on pale mushrooms. Soon, the shooting, strafing and explosions begin.

As in the 1984 original, the heroes are predominantly teenagers - mostly members of a high school football team - led, in this superficially updated version, by a soldier who had fought in the Iraq War.

.

The premise is that enemy forces - North Koreans and Russians - have invaded the USA without warning. It quickly becomes an all-out occupation. People are taken prisoner, and most choose to fearfully cooperate. But not these feisty teenagers. Under the tutelage of Jed (Chris Hemsworth), the older brother of Matt (Josh Peck), who plays on the Wolverines football team, they escape to the woods and learn to fight like the toughest Marines. Their training takes mere days. These teens are soon firing all manner of weapons, setting up elaborate ambushes and detonating bombs as if they were seasoned combat veterans.

But there's never any real depiction of how these kids are actually coping, separated from family, friends and any vestige of their former lives. Are they scared, determined, ambivalent? The movie doesn't bother to go there. Similarly, collaborators choose their path with no explanation.

Thor star Hemsworth is credible as the unofficial leader of the overnight soldiers, convincing as an action hero and believable in his über-patriotic speechifying. Peck as his brother is far less effective, with an acting style that would be better suited to a remake of Bill and Ted's Excellent Adventure.

The fighters begin to resemble a rural militia, dubbing themselves the Wolverines. It's essentially a shoot-'em-up spectacle devoid of any moral complexity.

Fire first and never ask questions seems to be their motto.

The film features some taut action sequences, well choreographed by director Dan Bradley, who is also one of the top stunt coordinators in the industry. But scenes are rather murkily shot and characters are like cardboard cutouts.

These young guerrillas eventually meet up with a trio of roving Marines. Oddly, they are the only hint of national military forces around, though their leader (Jeffrey Dean Morgan) speaks of swaths of unoccupied territory "from Alabama to Arizona and Michigan to Montana." Apparently, the invading evildoers are scared off by alliteration.

Only those with paranoid fantasies of an en masse invasion on American soil will find Red Dawn remotely powerful. The concept should have been updated to allow for more complex and surreptitious kinds of warfare.